Marine Reach chief executive and volunteer Jesse Misa said their mission, Project Hope, was to help as many people in the Pacific as possible.
"We cannot even begin to imagine the needs out there," Mr Misa said. "We are hoping to touch at least 20,000 people with our services on board. It's a whole medical programme that we take for granted here in our country."
Marine Reach has helped people in need of medical care in the Islands for 25 years.
Mr Misa said during that period they had provided more than $50 million worth of free services to 500,000 people.
Last year, close to 3000 Kiwis donated towards the project.
"I say this without any qualms - Kiwis are so generous, because they give out of their own need.
"For the past 25 years Kiwis have given and expected nothing back. They give a little but they're changing people's lives.
"They're the real unsung heroes here."
He said a major sponsorship programme from the United States also funded the project helping pay for fuel and the ship's upkeep.
"Corporations to private and individual sponsors from all walks of life have given towards our mission," Mr Misa said.
Tauranga locals Debbie Cuningham and Alison Cornwell donated their time and money towards the ship and its mission, and said the project was also important for Tauranga city.
Mrs Cornwell said local support showed people in Tauranga thought outside the box and less about themselves.
"This is something that's great for Tauranga too, it shows the people here have got behind the cause and are wanting to help others," Mrs Cornwell said.
Mrs Cuningham said she had seen first hand what the quality of life was like in the Islands and Marine Reach's mission was going to change lives.
"It's just amazing knowing how much of a difference this is going to make to people's lives," she said.
"This isn't about us but it's about the people in the Pacific who need help for a better life, we are just the hands and feet."
